共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
A. D. Munshi Bishwajit Panda Bikash Mandal I. S. Bisht E. S. Rao Ravinder Kumar 《Euphytica》2008,164(2):501-507
The genetics of resistance to Cucumber mosaic virus (CMV) in Cucumis sativus var. hardwickii R. Alef, the wild progenitor of cultivated cucumber was assessed by challenge inoculation and by natural infection of CMV.
Among the 31 genotypes of C. sativus var. hardwickii collected from 21 locations in India the lowest mean percent disease intensity (PDI) was recorded in IC-277048 (6.33%) while
the highest PDI was observed in IC-331631 (75.33%). All the four cultivated varieties (DC-1, DC-2, CHC-1 and CHC-2) showed
very high PDI and susceptible disease reaction. Based on mean PDI, 8 genotypes were categorized as resistant, 13 as moderately
resistant, 9 as moderately susceptible and one as susceptible. A chi-square test of frequency distribution based on mean PDI
in F2 progenies of six resistant × susceptible crosses revealed monogenic recessive Mendelian ratio 1(R):3(S) to be the best fit.
This monogenic recessive model was further confirmed by 1(R):1(S) ratio as the best fit for back cross with resistant parent
and no fit for either 3:1 or 1:1 in the back cross with the susceptible parent. The results revealed that CMV resistance in
C. sativus var. hardwickii was controlled by a single recessive gene. Considering the cross compatibility between C. sativus var. hardwickii and cultivated cucumber, the resistance trait can be easily transferred to cultivated species through simple backcross breeding. 相似文献
3.
Cucumber green mottle mosaic virus (CGMMV) is a severe threat for cucumber production worldwide. At present, there are no cultivars available in the market which show an effective resistance or tolerance to CGMMV infection, only wild Cucumis species were reported as resistant. Germplasm accessions of Cucumis sativus, as well as C. anguria and C. metuliferus, were mechanically infected with the European and Asian strains of CGMMV and screened for resistance, by scoring symptom severity, and conventional RT-PCR. The viral loads of both CGMMV strains were determined in a selected number of genotypes using quantitative RT-PCR. Severe symptoms were found following inoculation in C. metuliferus and in 44 C. sativus accessions, including C. sativus var. hardwickii. Ten C. sativus accessions, including C. sativus var. sikkimensis, showed intermediate symptoms and only 2 C. sativus accessions showed mild symptoms. C. anguria was resistant to both strains of CGMMV because no symptoms were expressed and the virus was not detected in systemic leaves. High amounts of virus were found in plants showing severe symptoms, whereas low viral amounts found in those with mild symptoms. In addition, the viral amounts detected in plants which showed intermediate symptoms at 23 and 33 dpi, were significantly higher in plants inoculated with the Asian CGMMV strain than those with the European strain. This difference was statistically significant. Also, the amounts of virus detected over time in plants did not change significantly. Finally, the two newly identified partially resistant C. sativus accessions may well be candidates for breeding programs and reduce the losses produced by CGMMV with resistant commercial cultivars. 相似文献
4.
A complete diallel cross study of six local populations of Iranian melon (Eyvanaki, Abasali, Tashkandi, Hose-sorkh, Mashhadi
and Nahavand) and one foreign cultivar (Ananasi) was carried out. We investigated maturity, average weight per fruit, yield
and acceptable yield in the pruning conditions over a period of two planting seasons. The analysis of variance for all of
the characteristics indicated highly significant differences among genotypes. Additive gene effects were most important with
respect to average weight per fruit and yield, while genetic dominance effects mainly controlled fruit maturity and acceptable
yield. The reciprocal effects were significant for yield, acceptable yield and fruit maturity. Nahavand and Tashkandi had
significant positive general combining ability effects for yield and acceptable yield. Favourable heterosis over the better
parent was found for average weight per fruit, yield and acceptable yield. Thus, there is the potential to generate superior
cultivars in segregant generation and hybrid production. 相似文献
5.
Melon (Cucumis melo L.) fruit production in U.S. can be improved through the introgression of early fruit maturity (FM) and the enhancement of
fruit color [i.e., quantity of β-carotene (QβC); orange mesocarp]. However, the genetics of FM and QβC have not been clearly
defined in U.S. Western Shipping market class melons (USWS). Thus, a cross was made between the monoecious, early FM Chinese
line ‘Q 3-2-2’ (non-carotene accumulating, white mesocarp) and the andromonecious, comparatively late FM USWS line ‘Top Mark’
(carotene accumulating; orange mesocarp) to determine the inheritance of FM and QβC in melon. Parents and derived cross-progenies
(F1, F2, F3, BC1P1, and BC1P2) were evaluated for FM and QβC at Hancock, Wisconsin over 2 years. Estimates of narrow-sense heritability (h
N2) for QβC and FM as defined by F1, F2, and BC (by individuals) were 0.55 and 0.62, respectively, while estimates based on F3 families were 0.68 and 0.57, respectively for these traits. Mesocarp color segregation (F2 and BC1P2) fit a two gene recessive epistatic model, which in turn, interacts with other minor genes. Although the inheritance of QβC
and FM is complex, introgression (e.g., by backcrossing) of early FM genes resident in Chinese germplasm into USWS market
types is possible. Such introgression may lead to increased yield potential in USWS market types while retaining relatively
high β-carotene fruit content (i.e., orange mesocarp), if stringent, multiple location and early generation family selection
(F3–4) is practiced for FM with concomitant selection for QβC. 相似文献
6.
Aneeta Pradhan Julie A. Plummer Matthew N. Nelson Wallace A. Cowling Guijun Yan 《Euphytica》2010,176(1):87-98
A triploid hybrid with an ABC genome constitution, produced from an interspecific cross between Brassica napus (AACC genome) and B. nigra (BB genome), was used as source material for chromosome doubling. Two approaches were undertaken for the production of hexaploids:
firstly, by self-pollination and open-pollination of the triploid hybrid; and secondly, by application of colchicine to axillary
meristems of triploid plants. Sixteen seeds were harvested from triploid plants and two seedlings were confirmed to be hexaploids
with 54 chromosomes. Pollen viability increased from 13% in triploids to a maximum of 49% in hexaploids. Petal length increased
from 1.3 cm (triploid) to 1.9 cm and 1.8 cm in the two hexaploids and longest stamen length increased from 0.9 cm (triploid)
to 1.1 cm in the hexaploids. Pollen grains were longer in hexaploids (43.7 and 46.3 μm) compared to the triploid (25.4 μm).
A few aneuploid offsprings were also observed, with chromosome number ranging from 34 to 48. This study shows that trigenomic
hexaploids can be produced in Brassica through interspecific hybridisation of B. napus and B. nigra followed by colchicine treatment. 相似文献
7.
8.
Gabriela de Oliveira Belo Margarete Magalhães Souza Gonçalo Santos Silva Manuella Palmeira Lavinscky 《Euphytica》2018,214(1):2
Two new varieties of interspecific hybrids of Passiflora have been developed from the cross between P. gardneri versus P. gibertii, both registered under the Passiflora Society International. Twelve putative hybrids were analyzed. Hybridization was confirmed using RAPD and SSR markers. Primer UBC11 (5′-CCGGCCTTAC-3′) generated informative bands. Primer SSR Pe75 has amplified species-specific fragments and a heterozygote status was observed with two parent bands 300 and 350 bp. The molecular markers generated have been analyzed for the presence or absence of specific informative bands. Based on the morphological characterization, we have identified two hybrid varieties: P. ‘Gabriela’ and P. ‘Bella’. P. ‘Gabriela’ produced flowers in bluish tones, bluish petals on the adaxial and abaxial faces, light blue sepals on the adaxial and light green on the abaxial faces, corona with the base of filaments in intense lilac color and white apex. P. ‘Bella’ produced flowers in lilac tones, intense lilac petals on the adaxial and abaxial faces, dark lilac sepals with whitish edges on the adaxial and light green on the abaxial faces, corona with the base of filaments in intense lilac color and white apex. The cytogenetic analysis verified that the hybrids have the same chromosomal number as the parents (2n = 18); the formation of bivalents between the homeologous chromosomes (n = 9) was observad, leading to regular meiosis, which allows the sexual reproduction and use of these hybrids in breeding programs. 相似文献
9.
P. Kaushal Aarti Khare S. A. Siddiqui A. Agrawal Sharmishtha Paul D. R. Malaviya A. K. Roy S. N. Zadoo 《Euphytica》2010,174(2):261-281
New tri-species hybrids (GOS) in the genus Pennisetum involving the cultivated species pearl millet (P. glaucum L.) and two wild species, viz. P. squamulatum Fresen and P. orientale L. C. Rich, are reported. Six hybrid plants were recovered after crossing a backcross hybrid (2n = 3x = 23, GGO) between P. glaucum (2n = 2x = 14, GG) and P. orientale (2n = 2x = 18, OO) with F1s (2n = 6x = 42, GGSSSS) between P. glaucum (2n = 4x = 28, GGGG) and P. squamulatum (2n = 8x = 56, SSSSSSSS). The hybrids were perennial, morphologically intermediate to their parents, and represented characters from the three contributing
species. The hybrids contained 2n = 44 chromosomes (GGGSSO) representing 21, 14 and nine chromosomes from P. glaucum, P. squamulatum and P. orientale, respectively. Meiotic and flow-cytometric analysis suggested origin of these hybrids from unreduced female and reduced male
gametes. Average chromosome configuration (8.42I + 14.32II + 1.62III + 0.52IV) at Meiosis showed limited inter-genomic pairing indicating absence of significant homology between the three genomes. The
hybrids were male sterile (except one) and highly aposporous. P. orientale was identified to induce apospory in hybrid background with P. glaucum at diploid and above levels, though it was quantitatively affected by genomic doses from sexual parent. A case of inducible
and recurrent apospory is presented whereby a transition from Polygonum-type sexual embryo-sacs to Panicum-type aposporous
embryo-sacs was observed in diploid interspecific hybrids. Results supported independent origin and partitioning of the three
apomixis-components (apomeiosis, parthenogenesis, and functional endosperm development), reported for the first time in Pennisetum. Potential utilization of GOS hybrids in understanding genome interactions involved in complex traits, such as perenniality
and apomixis, is discussed. 相似文献
10.
Yue Jin 《Euphytica》2011,179(1):105-108
The common barberry and several other Berberis spp. serve as the alternate hosts to two important rust pathogens of small grains and grasses, Puccinia graminis and P. striiformis. Barberry eradication has been practiced for centuries as a means to control stem rust. Diverse virulence variations have
been observed in populations of P. graminis f. sp. tritici that were associated with susceptible barberries in North America. Barberry likely has played a role in generating new races
of P. striiformis f. sp. tritici in some regions in the world. Several North American stem rust races, namely races 56, 15B and QCC, initially originated
from barberry, were subsequently responsible for generating large-scale epidemics. Thus, sexual cycles on Berberis spp. may generate virulence combinations that could have serious consequences to cereal crop production. 相似文献
11.
Phytophthora root rot caused by Phytophthora drechsleri Tucker is one of the most devastating sugar beet diseases in tropical areas. To identify genetic resources resistant to this disease, an aggressive isolate of P. drechsleri was selected. Then, a screening method was optimized based on the standard scoring scales of 1–9 (1: no symptoms, 9: complete plant death). Finally, 19 sugar beet lines, three cultivars, and 14 accessions of the wild species Beta vulgaris subsp. maritima, B. macrocarpa, B. procumbens, and B. webbiana were evaluated for resistance to the most aggressive isolate of P. drechsleri by using the optimized method (inoculum included 20 g of rice seed together with superficial wound creation). The isolates of P. drechsleri had significant variation in aggressiveness, and Kv10 was the most aggressive isolate on the susceptible variety Rasoul. The lines O.T.201-15, SP85303-0 (resistant check), and S2-24.P.107 had the lowest disease index with scores of 3.09, 3.13, and 3.27 respectively; they were categorized into the resistant group. The interaction between isolates and genotypes was not significant, which indicated the same response of each genotype to different isolates. Investigating the resistance of different generations of sugar beet revealed that progeny selection would be an effective method for increasing the resistance level of breeding materials to P. drechsleri. Among the wild species, the accession 9402 belonging to B. macrocarpa and the accession 7234 of B. vulgaris subsp. maritima had the lowest disease index (2.29 and 2.60, respectively) and were categorized into the resistant group. 相似文献
12.
Lu Xiao Bin Yi Yufeng Chen Zhen Huang Wei Chen Chaozhi Ma Jinxing Tu Tingdong Fu 《Euphytica》2008,164(2):377-384
7–7365AB is a recessive genic male sterile (RGMS) two-type line, which can be applied in a three-line system with the interim-maintainer,
7–7365C. Fertility of this system is controlled by two duplicate dominant epistatic genes (Bn;Ms3 and Bn;Ms4) and one recessive epistatic inhibitor gene (Bn;rf). Therefore an individual with the genotype of Bn;ms3ms3ms4ms4Rf_ exhibits male sterility, whereas, plant with Bn;ms3ms3ms4ms4rfrf shows fertility because homozygosity at the Bn;rf locus (Bn;rfrf) can inhibit the expression of two recessive male sterile genes in homozygous Bn;ms3ms3ms4ms4 plant. A cross of 7–7365A (Bn;ms3ms3ms4ms4RfRf) and 7–7365C (Bn;ms3ms3ms4ms4rfrf) can generate a complete male sterile population served as a mother line with restorer in alternative strips for the multiplication
of hybrid seeds. In the present study, molecular mapping of the Bn;Rf gene was performed in a BC1 population from the cross between 7–7365A and 7–7365C. Bulked segregant analysis (BSA) and amplified fragment length polymorphism
(AFLP) technique was used to identify molecular markers linked to the gene of interest. From a survey of 768 primer combinations,
seven AFLP markers were identified. The closest marker, XM5, was co-segregated with the Bn;Rf locus and successfully converted into a sequence characterized amplified region (SCAR) marker, designated as XSC5. Two flanking
markers, XM3 and XM2, were 0.6 cM and 2.6 cM away from the target gene, respectively. XM1 was subsequently mapped on linkage
group N7 using a doubled-haploid (DH) mapping population derived from the cross Tapidor × Ningyou7, available at IMSORB, UK.
To further confirm the location of the Bn;Rf gene, additional simple sequence repeat (SSR) markers in linkage group N7 from the reference maps were screened in the BC1 population. Two SSR markers, CB10594 and BRMS018, showed polymorphisms in our mapping population. The molecular markers found
in the present study will facilitate the selection of interim-maintainer. 相似文献
13.
Coffee varieties with resistance for the plant-parasitic nematodes Pratylenchus coffeae and Radopholus arabocoffeae are limited in Vietnam. A selection of imported varieties and high yield varieties of Arabica coffee in Vietnam were evaluated
for resistance to both plant-parasitic nematode species in Northern Vietnam. The same experiments were carried out with hybrid
arabica coffee, three selected clones of Coffea
canephora and one clone of Coffea excelsa in the Western Highland of Vietnam. The screened coffee accessions from Ethiopia (KH1, KH13, KH20, KH21, KH29, and KH31)
were susceptible and good host for P. coffeae. Also accessions 90P4 (Portugal) and Oro azteca (Mexico) had a reproduction factor Rf > 1. Pluma Hidalgo (Mexico), 90/6 (Vietnam), 90P3 (Portugal), 90P2 (Vietnam), Variedad (Mexico), 90T (Portugal), and Garnica
(Mexico) were poor hosts (Rf < 1) but not tolerant to P. coffeae, expressed by a reduction of root weight compared to untreated control plants. Most of the coffee accessions tested in Northern
Vietnam were intolerant to R. arabocoffeae, except 90T which showed no reduction of root weight, even at high initial nematode densities (4,000/pot). Good hosts for
R. arabocoffeae were Variedad, KH1, KH21, KH29, KH20, KH31, and KH13 with Rf > 1. Pluma Hidalgo, 90/6, 90P3, 90P2, 90T, Oro azteca, and Garnica were poor hosts (Rf < 1). In the Western Highland experiment, all arabica coffee accessions were susceptible for P. coffeae with Rf ranging from 1.41 to 1.59. Tolerance to P. coffeae was found in C. liberica var. Dewevrei, Hong34 and Nhuantren. Coffea excelsa, Hong34, Nhuantren, and H1C19 were tolerant to R. arabocoffeae at the highest inoculation density (4,000 nematodes/pot). The most susceptible accessions were Nhuantren and K55. Resistance
(Rf < 1) to R. arabocoffeae was found in C. liberica var. Dewevrei and Hong34. This article reports on the first screening for resistance and tolerance to P. coffeae and R. arabocoffeae in coffee accessions in Vietnam and shows promising results for enhanced coffee-breeding. 相似文献
14.
Pseudomonas syringae is the main pathogen responsible for bacterial blight disease in pea and can cause yield losses of 70%. P. syringae pv. pisi is prevalent in most countries but the importance of P. syringae pv. syringae (Psy) is increasing. Several sources of resistance to Psy have been identified but genetics of the resistance is unknown. In this study the inheritance of resistance to Psy was studied in the pea recombinant inbred line population P665 × ‘Messire’. Results suggest a polygenic control of the resistance and two quantitative trait loci (QTL) associated with resistance, Psy1 and Psy2, were identified. The QTL explained individually 22.2 and 8.6% of the phenotypic variation, respectively. In addition 21 SSR markers were included in the P665 × ‘Messire’ map, of which six had not been mapped on the pea genome in previous studies. 相似文献
15.
16.
Junghyun Shim Olivier Panaud Clémentine Vitte Merlyn S. Mendioro Darshan S. Brar 《Euphytica》2010,176(2):269-279
Molecular markers have been successfully used in rice breeding however available markers based on Oryza
sativa sequences are not efficient to monitor alien introgression from distant genomes of Oryza. We developed O. minuta (2n = 48, BBCC)-specific clones comprising of 105 clones (266–715 bp) from the initial library composed of 1,920 clones against
O. sativa by representational difference analysis (RDA), a subtractive cloning method and validated through Southern blot hybridization.
Chromosomal location of O. minuta-specific clones was identified by hybridization with the genomic DNA of eight monosomic alien additional lines (MAALs). The
37 clones were located either on chromosomes 6, 7, or 12. Different hybridization patterns between O. minuta-specific clones and wild species such as O. punctata, O. officinalis, O. rhizomatis, O. australiensis, and O. ridleyi were observed indicating conservation of the O. minuta fragments across Oryza spp. A highly repetitive clone, OmSC45 hybridized with O. minuta and O. australiensis (EE), and was found in 6,500 and 9,000 copies, respectively, suggesting an independent and exponential amplification of the
fragment in both species during the evolution of Oryza. Hybridization of 105 O. minuta specific clones with BB- and CC-genome wild Oryza species resulted in the identification of 4 BB-genome-specific and 14 CC-genome-specific clones. OmSC45 was identified as a fragment of RIRE1, an LTR-retrotransposon. Furthermore this clone was introgressed from O. minuta into the advanced breeding lines of O. sativa. 相似文献
17.
Interspecific hybridization was carried out between Lilium longiflorum and L. lophophorum var. linearifolium by using the cut style method of pollination, as a contrast, intraspecific hybridization between L. longiflorum ‘Gelria’ and L. longiflorum was also made, but no mature seeds and offspring were obtained from the two combinations under in vivo condition. Ovules
excised from each carpel 5–35 days after pollination (DAP) were cultured on B5 or half-strength B5 medium containing sucrose
at different concentrations in vitro. In L. longiflorum × L. lophophorum var. linearifolium, only 1.17% of ovules excised at 10 DAP developed into seedlings, and in L. longiflorum ‘Gelria’ × L. longiflorum, only 0.99% of ovules excised at 25 DAP developed into seedlings; none of the ovules excised at other different DAP in the
two cross combinations produced any seedlings. The results showed that interspecific hybridization had a more serious post-fertilization
barrier than the intraspecific hybridization, and that a lower concentration (3%) of sucrose led to better embryo development
and higher percentage of seedlings in ovule cultures. All hybrid seedlings obtained were successfully transplanted to soil
and grew normally. The progenies investigated were identified as true hybrids based on inter-simple sequence repeat (ISSR)
analysis. 相似文献
18.
We have previously reported that expression of salt-responsive genes, including Bruguiera gymnorhiza
ankyrin repeat protein 1 (BgARP1), enhances salt tolerance in both Agrobacterium tumefaciens and Arabidopsis. In this report, we further characterized BgARP1-expressing Arabidopsis to elucidate the role of BgARP1 in salt tolerance. BgARP1-expressing plants exhibited more vigorous growth than wild-type plants on MS plates containing 125–175 mM NaCl. Real-time
PCR analysis showed enhanced induction of osmotin34 in the 2-week-old transformants under 125 mM NaCl. It was also showed that induction of typical salt-responsive genes, including
RD29A, RD29B, and RD22, was blunted and delayed in the 4-week-old transformants during 24 h after 200 mM NaCl treatment. Ion content analysis showed
that transgenic plants contained more K+, Ca2+, and NO3
−, and less NH4
+, than wild-type plants grown in 200 mM NaCl. Our results suggest that BgARP1-expressing plants may reduce salt stress by up-regulating osmotin34 gene expression and maintaining K+ homeostasis and regulating Ca2+ content. These results indicate that BgARP1 is functional on a heterogeneous background. 相似文献
19.
Noelle Giacomini Lemos Alessandro de Lucca e Braccini Ricardo Vilela Abdelnoor Maria Cristina Neves de Oliveira Kazuhiro Suenaga Naoki Yamanaka 《Euphytica》2011,182(1):53-64
Asian rust, caused by the fungus Phakopsora pachyrhizi, is the most severe disease currently threatening soybean crops in Brazil. The development of resistant cultivars is a top
priority. Genetic characterization of resistance genes is important for estimating the improvement when these genes are introduced
into soybean plants and for planning breeding strategies against this disease. Here, we infected an F2 population of 140 plants derived from a cross between ‘An-76’, a line carrying two resistance genes (Rpp2 and Rpp4), and ‘Kinoshita’, a cultivar carrying Rpp5, with a Brazilian rust population. We scored six characters of rust resistance (lesion color [LC], frequency of lesions having
uredinia [%LU], number of uredinia per lesion [NoU], frequency of open uredinia [%OU], sporulation level [SL], and incubation
period [IP]) to identify the genetic contributions of the three genes to these characters. Furthermore, we selected genotypes
carrying these three loci in homozygosis by marker-assisted selection and evaluated their genetic effect in comparison with
their ancestors, An-76, PI230970, PI459025, Kinoshita and BRS184. All three genes contributed to the phenotypes of these characters
in F2 population and when pyramided, they significantly contributed to increase the resistance in comparison to their ancestors.
Rpp2, previously reported as being defeated by the same rust population, showed a large contribution to resistance, and its resistance
allele seemed to be recessive. Rpp5 had the largest contribution among the three genes, especially to SL and NoU. Only Rpp5 showed a significant contribution to LC. No QTLs for IP were detected in the regions of the three genes. We consider that
these genes could contribute differently to resistance to soybean rust, and that genetic background plays an important role
in Rpp2 activity. All three loci together worked additively to increase resistance when they were pyramided in a single genotype
indicating that the pyramiding strategy is one good breeding strategy to increase soybean rust resistance. 相似文献
20.
Franceli R. Kulcheski Felipe A. S. Graichen José A. Martinelli Ana B. Locatelli Luiz C. Federizzi Carla A. Delatorre 《Euphytica》2010,175(3):423-432
Crown rust, which is caused by Puccinia
coronata f. sp. avenae, P. Syd. & Syd., is the most destructive disease of cultivated oats (Avena
sativa L.) throughout the world. Resistance to the disease that is based on a single gene is often short-lived because of the extremely
great genetic diversity of P. coronata, which suggests that there is a need to develop oat cultivars with several resistance genes. This study aimed to identify
amplified fragment length polymorphism AFLP markers that are linked to the major resistance gene, Pc68, and to amplify the F6 genetic map from Pc68/5*Starter × UFRGS8. Seventy-eight markers with normal segregation were discovered and distributed in
12 linkage groups. The map covered 409.4 cM of the Avena
sativa genome. Two AFLP markers were linked in repulsion to Pc68: U8PM22 and U8PM25, which flank the gene at 18.60 and 18.83 centiMorgans (cM), respectively. The marker U8PM25 is located
in the linkage group 4_12 in the Kanota × Ogle reference oat population. These markers should be useful for transferring Pc68 to genotypes with good agronomic characteristics and for pyramiding crown rust resistance genes. 相似文献